A dispute over a basement fire may have prompted a University of Maryland graduate student early Tuesday to shoot two housemates, one fatally, then turn the gun on himself, police said.
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The deadly incident began about 1 a.m. Tuesday outside a home in the 8700 block of 36th Avenue, a dead-end street of modest split-levels, most of them rented by students, about a block from campus.

Prince George’s County police said investigators believe that the graduate student lit a fire in the basement of the house, for reasons that were not made clear. His two housemates confronted him about it, authorities said.

All three men then went outside to the front of the house, where the student who had started the blaze shot one of the housemates, police said. As the second housemate tried to flee, the gunman shot him as well, police said. He then reportedly went to the back of the house and turned the gun on himself.